Hello Chrizyyy, please Update Firefox to the latest version and if the issue continues in order to assist you better, please follow the steps below to provide us crash ID's to help us learn more about your crash.

1. Enter about:crashes in the address bar (that's where you enter your website URL) and press Enter. You should now see a list of submitted crash reports.
2. Copy the 5 most recent crash ID's that you see in the crash report window and paste them into your response here.

Thank you for your cooperation!

More information and further troubleshooting steps can be found in the Troubleshoot Firefox crashes (closing or quitting unexpectedly) article.

I actually have the same problem. Firefox crashes whenever I initiate a download when the memory (RAM) is at a very low level (approx 100MB free).

Below are some of the crash reports: bp-20f5f680-d590-4137-a720-2c1c62130803 F146B519-3B7C-4A54-8DC3-ED4988D10965 bp-8419e62b-4305-470c-822d-d60c42130728 bp-db276066-3461-4b52-8a6b-3014f2130718 bp-5177bdc1-c602-4d9d-b74e-0b89e2130605

Thanks,